Patch "iommu/arm-smmu-v3: Don't free page table ops twice" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

iommu/arm-smmu-v3: Don't free page table ops twice

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
iommu-arm-smmu-v3-don-t-free-page-table-ops-twice.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Jean-Philippe Brucker <[email protected]>
Date: Thu, 14 Dec 2017 11:03:01 +0000
Subject: iommu/arm-smmu-v3: Don't free page table ops twice

From: Jean-Philippe Brucker <[email protected]>

commit 57d72e159b60456c8bb281736c02ddd3164037aa upstream.

Kasan reports a double free when finalise_stage_fn fails: the io_pgtable ops are freed by arm_smmu_domain_finalise and then again by arm_smmu_domain_free. Prevent this by leaving pgtbl_ops empty on failure.

---
 drivers/iommu/arm-smmu-v3.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

@@ -1541,13 +1541,15 @@ static int arm_smmu_domain_finalise(stru
 		return -ENOMEM;
 
 	arm_smmu_ops.pgsize_bitmap = pgtbl_cfg.pgsize_bitmap;
-	smmu_domain->pgtbl_ops = pgtbl_ops;
 
 	ret = finalise_stage_fn(smmu_domain, &pgtbl_cfg);
-	if (IS_ERR_VALUE(ret))
+	if (IS_ERR_VALUE(ret)) {
 		free_io_pgtable_ops(pgtbl_ops);
+		return ret;
+	}
 
-	return ret;
+	smmu_domain->pgtbl_ops = pgtbl_ops;
+	return 0;
 }
 
 static struct arm_smmu_group *arm_smmu_group_get(struct device *dev)

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/iommu-arm-smmu-v3-don-t-free-page-table-ops-twice.patch